This proposal requests funds for travel and per diem for forty-five (45) participants to the Fourth Symposium on Epidemiology and Cancer Registries in the Pacific Basin. The first three (1975, 1978, 1981) provided a forum for the exchange of information on the design and conduct of cancer registries, and the status of research in cancer epidemiology in nineteen participating countries and territories of the Pacific. In addition, important collaborative research on several cancers (e.g., lung, breast, melanoma, nasopharynx, liver, and colo-rectal) was developed. The Fourth Symposium will be designed to provide further comparative cancer incidence data on the major ethnic groups in the Pacific Basin. New cancer statistics will be available from the Polynesian, Melanesian and Micronesian populations of the South Pacific Commission Region and from the People's Republic of China. The status of completed as well as ongoing collaborative research projects will be reviewed and new projects will be designed during workshops focused on etiological mechanisms. Special sessions will be devoted to a review of studies in the Pacific Basin that are focused on possible methods of chemoprevention (e.g. vitamin A, C and E, Beta carotene) and radiation carcinogenesis.